To the lance armstrong interview with oprah now and the one question that broke him down. Was it a glimpse of the man behind the lying? Did it make any difference for investigators watching, too. Reporter: We know that living a lie and pulling off one of the greatest cheating scandals in sport was as much a part of armstrong's dna as much as riding a bike. He had to come to a crossroads when he had to admit his own son that he had been lying. I saw my son defending me and saying that's not true. That's when I knew that I had to tell him. I said -- don't defend me anymore. Reporter: Tyler hamilton, a former teammate and friend bitterly attacked, and even threatened for telling the truth, now said that he's now seeing a side of armstrong unlike anything he has ever seen. These last two nights, it's like the new lance. The lance he hoped to be and the old lance. You can see it. It's like a battle. This is heavy. And this is messy and this is not something that I can sit with you and leave and go, okay. Reporter: Armstrong told oprah that he's now in therapy and sees how, quote, sick some of his actions were. But it just some old version of himself. That arrogant twitter photo boasting of his tour wins, even after he had been stripped, was just two months ago. That was just, more defiance. And you know what's scary is, i actually thought it was a good idea. Reporter: He acknowledged that his ex-wife knew of his cheating and encouraged him not only to stop but to come clean. He never did until he lost everything and was back in a corner. Will you rise again? I do not. Neal is here with us. In new york. Neal, you talked about with anti-doping officials who watched this interview, has it made any difference for him? In a word, no. They said that he has to come forward under oath, with names, dates. Pass the drug test, they said there have been talks about coming in before the oprah interview. Those have since stalled.

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